If you go down to the boardwalk at the foot of Spadina on a sunny day and peer over the edge, you’ll see something that seemed unimaginable even a decade ago: the shadows of darting fish. Both the number and diversity have soared in the past few years because of an underwater structure of boulders, logs and stumps, covered in a thick rug of aquatic plants—an ideal hangout for walleye, northern pike and largemouth bass. The man-made habitats—nicknamed “fish ­condos”—abut concrete walls where Waterfront Toronto built new boardwalks at the Spadina, Simcoe and Rees slips in 2008 and 2009. Underwater creatures adore the murky nooks and cubbyholes, and are thriving due to a recent improvement in the water quality, which has come a long way from the noxious swill of decades past. Should you manage to snag a fish-condo resident with a hook and line, it’s even safe to take home and eat for dinner.